The present invention concerns a plug connector for releasable connection of a pressurized line, consisting of a housing body with a receiving opening to insert one end of the line, and with an inner sleeve attached in the housing body in an arrangement that extends coaxially within the receiving opening for engagement into the inserted line end, in which a clamping element is mounted to move axially in the receiving opening,.so that it cooperates with an inner conical surface of the housing body to hold the line and in so doing, acts radially inward with at least one retaining edge in form-fit or friction- and form-fit fashion against the outer periphery of the line.
This type of plug connector for pipelines and/or hose lines with a smooth outer peripheral surface is known from EP 0 247 214 B1. To seal the line connection, it is proposed that the sleeve-like, chuck-like clamping element be sealed on its end facing the insertion opening radially outward against the wall of the housing-receiving opening, as well as radially inward against the line by means of a sealing ring. These sealing rings are then connected to the clamping element in bonded fashion. The inner sleeve secured in the housing body via a snap connection engages in it with peripheral play for radial support of the line, since its outside diameter should be slightly smaller than the inside diameter of the line. This plug connector has essentially proven itself, but the seals connected to the clamping element in bonded fashion require costly manufacture.
A similar line coupling is known from EP 0 373 272 B1 (especially FIG. 9), which, however, is also quite costly to manufacture, since it consists of numerous individual parts. Two sealing rings are provided for sealing, which act on the outer periphery of the inserted line. In other embodiments, the inner sleeve engages in the line with a number of annular edges. This guarantees mechanical securing of the line; a clamping element, acting in the generic sense on the outer periphery of the line, is not provided here.
In addition, a similar connector had already been proposed, in which the inner sleeve engages in sealing fashion in the line, with a torus. However, it is prescribed therein that the clamping element, which can be moved to loosen or release the line and the inner sleeve with torus are adapted to each other and cooperate, so that during displacement of the clamping element, the torus is caused to engage in the line in sealing fashion or to be released or loosened from the interior of the line. This expedient, however, requires mobility, and for this purpose, at least partial axial slotting of the inner sleeve, so that the torus alone is not sufficient for sealing. Instead, a seal must additionally be present between the clamping element and the housing body, which must permit axial relative movements. A version that is demanding, in terms of design and manufacture, is therefore also involved.
The underlying task of the present invention is to devise a plug connector of the generic type described at the outset, which is characterized by simple and cost-effective design and manufacture.
This is achieved according to the invention in that the inner sleeve is fastened in the housing body media-tight around the periphery via connection means and preferably engages in the line media-tight around the periphery with means of sealing. Thus, according to the invention, media-tight sealing outward is guaranteed merely by the sealing engagement of the essentially rigidly secured inner sleeve in the line, because the inner sleeve itself is also tightly joined to the housing body. Special connection means are prescribed for this purpose, which can be made very simply and cost-effectively in different shapes. Some advantageous embodiments of this are described below.
The inner sleeve preferably has at least one sealing torus on its outer periphery as means of sealing. In this region and in the region axially between the sealing torus and the sealing connection of the inner sleeve with the housing body, the inner sleeve is essentially rigid and completely closed, i.e., designed without axial/radial wall openings, so that a sealing line connection is guaranteed without additional seals acting, for example, on the outer periphery of the line. The sealing torus according to the invention is adapted with respect to its outside diameter to the inside cross section of the line, so that the line can be mounted onto the inner sleeve or withdrawn from it again by frictional closure, in which internal sealing is guaranteed in the mounted state by frictional retention of the line on the sealing torus. The line can therefore advantageously be inserted quickly and simply and at any time, released again by simple pulling, after the clamping element has also been brought into a loosening position that releases the outside periphery of the line.
Other advantageous configurations of the invention are contained in the subordinate claims, as well as the following description.